The overall objective of this project is to design, synthesis, and biological evaluation of novel epoxypolypeptides as potential inactivators of renin and prorenin. Specifically, the project involves the synthesis of analogues of the Leu-Leu-Val-Tyr sequence of angiotensinogen wherein an epoxide moiety is placed in position which approximates the Leu-Leu pept-de bond. The compounds are being evaluated in vitro for their ability to inactivate both renin and prorenin. It is hoped that the compounds will prove to be valuable tools in studies aimed at determining the role of the renin-angiotensin system in hypertension.